Phase separation of FSP1 promotes ferroptosis.

Ferroptosis is evolving as a highly promising approach to combat difficult-to-treat tumour entities including therapy-refractory and dedifferentiating cancers1-3. Recently, ferroptosis suppressor protein-1 (FSP1), along with extramitochondrial ubiquinone or exogenous vitamin K and NAD(P)H/H+ as an electron donor, has been identified as the second ferroptosis-suppressing system, which efficiently prevents lipid peroxidation independently of the cyst(e)ine-glutathione (GSH)-glutathione peroxidase 4 (GPX4) axis4-6. To develop FSP1 inhibitors as next-generation therapeutic ferroptosis inducers, here we performed a small molecule library screen and identified the compound class of 3-phenylquinazolinones (represented by icFSP1) as potent FSP1 inhibitors. We show that icFSP1, unlike iFSP1, the first described on-target FSP1 inhibitor5, does not competitively inhibit FSP1 enzyme activity, but instead triggers subcellular relocalization of FSP1 from the membrane and FSP1 condensation before ferroptosis induction, in synergism with GPX4 inhibition. icFSP1-induced FSP1 condensates show droplet-like properties consistent with phase separation, an emerging and widespread mechanism to modulate biological activity7. N-terminal myristoylation, distinct amino acid residues and intrinsically disordered, low-complexity regions in FSP1 were identified to be essential for FSP1-dependent phase separation in cells and in vitro. We further demonstrate that icFSP1 impairs tumour growth and induces FSP1 condensates in tumours in vivo. Hence, our results suggest that icFSP1 exhibits a unique mechanism of action and synergizes with ferroptosis-inducing agents to potentiate the ferroptotic cell death response, thus providing a rationale for targeting FSP1-dependent phase separation as an efficient anti-cancer therapy.

A non-canonical vitamin K cycle is a potent ferroptosis suppressor.

Ferroptosis, a non-apoptotic form of cell death marked by iron-dependent lipid peroxidation1, has a key role in organ injury, degenerative disease and vulnerability of therapy-resistant cancers2. Although substantial progress has been made in understanding the molecular processes relevant to ferroptosis, additional cell-extrinsic and cell-intrinsic processes that determine cell sensitivity toward ferroptosis remain unknown. Here we show that the fully reduced forms of vitamin K-a group of naphthoquinones that includes menaquinone and phylloquinone3-confer a strong anti-ferroptotic function, in addition to the conventional function linked to blood clotting by acting as a cofactor for γ-glutamyl carboxylase. Ferroptosis suppressor protein 1 (FSP1), a NAD(P)H-ubiquinone reductase and the second mainstay of ferroptosis control after glutathione peroxidase-44,5, was found to efficiently reduce vitamin K to its hydroquinone, a potent radical-trapping antioxidant and inhibitor of (phospho)lipid peroxidation. The FSP1-mediated reduction of vitamin K was also responsible for the antidotal effect of vitamin K against warfarin poisoning. It follows that FSP1 is the enzyme mediating warfarin-resistant vitamin K reduction in the canonical vitamin K cycle6. The FSP1-dependent non-canonical vitamin K cycle can act to protect cells against detrimental lipid peroxidation and ferroptosis.

Persistent autism-relevant behavioral phenotype and social neuropeptide alterations in female mice offspring induced by maternal transfer of PBDE congeners in the commercial mixture DE-71.

Polybrominated diphenyl ethers (PBDEs) are ubiquitous persistent organic pollutants (POPs) that are known neuroendocrine disrupting chemicals with adverse neurodevelopmental effects. PBDEs may act as risk factors for autism spectrum disorders (ASD), characterized by abnormal psychosocial functioning, although direct evidence is currently lacking. Using a translational exposure model, we tested the hypothesis that maternal transfer of a commercial mixture of PBDEs, DE-71, produces ASD-relevant behavioral and neurochemical deficits in female offspring. C57Bl6/N mouse dams (F0) were exposed to DE-71 via oral administration of 0 (VEH/CON), 0.1 (L-DE-71) or 0.4 (H-DE-71) mg/kg bw/d from 3 wk prior to gestation through end of lactation. Mass spectrometry analysis indicated in utero and lactational transfer of PBDEs (in ppb) to F1 female offspring brain tissue at postnatal day (PND) 15 which was reduced by PND 110. Neurobehavioral testing of social novelty preference (SNP) and social recognition memory (SRM) revealed that adult L-DE-71 F1 offspring display deficient short- and long-term SRM, in the absence of reduced sociability, and increased repetitive behavior. These effects were concomitant with reduced olfactory discrimination of social odors. Additionally, L-DE-71 exposure also altered short-term novel object recognition memory but not anxiety or depressive-like behavior. Moreover, F1 L-DE-71 displayed downregulated mRNA transcripts for oxytocin (Oxt) in the bed nucleus of the stria terminalis (BNST) and supraoptic nucleus, and vasopressin (Avp) in the BNST and upregulated Avp1ar in BNST, and Oxtr in the paraventricular nucleus. Our work demonstrates that developmental PBDE exposure produces ASD-relevant neurochemical, olfactory processing and behavioral phenotypes that may result from early neurodevelopmental reprogramming within central social and memory networks.

Association of persistent organic pollutants with sensorimotor neuropathy in participants with and without diabetes or prediabetes: Results from the population-based KORA FF4 study.

BACKGROUND: Concentrations of persistent organic pollutants (POPs) have been associated with an increased type 2 diabetes (T2D) risk. It remains unclear whether POPs are also associated with the risk of diabetes complications including neuropathy and evidence on this topic is scarce. We aimed to investigate the hypothesis that low-dose background concentrations of POPs were positively associated with distal sensorimotor polyneuropathy (DSPN). METHODS: This cross-sectional study was based on data from the second follow-up (FF4, 2013-2014, N = 2279) of the population-based KORA S4 study (Augsburg, Germany). The study sample consisted of 200 participants, including four groups of 50 persons each with known T2D, prediabetes, newly diagnosed diabetes, and normal glucose tolerance (NGT) based on an oral glucose tolerance test. We analyzed the association of six most abundant serum concentrations of POPs, including polychlorinated biphenyls (PCBs) as well as organochlorine (OC) pesticides, with DSPN by multivariable logistic regression adjusted for age, sex, glycaemic status, body mass index, physical activity, smoking and alcohol consumption. We assessed effect modification by age, sex, glycaemic status and obesity and conducted two-pollutant models to check the robustness of the estimates. RESULTS: For all pollutants, the main models indicated no significant association of having DSPN but pointed to rather decreased odds for DSPN. Two-pollutant models supported these findings, though only the association between the combination of PCB-138 and beta-hexachlorocyclohexane (ß-HCH) (OR: 0.59; 95% CI: 0.35-0.99) with DSPN became significant. No effect modification was found by age, sex, glycaemic status and obesity. CONCLUSION: Low-dose concentrations of POPs were not associated with increased odds of having DSPN in T2D, prediabetes and NGT.

Long-term effects of a catastrophic insecticide spill on stream invertebrates.

Accidental spills or illegal discharges of pesticides in aquatic ecosystems can lead to exposure levels that strongly exceed authorized pesticide concentrations, causing major impacts on aquatic ecosystems. Such short-term events often remain undetected in regular monitoring programs with infrequent sampling. In early spring 2015, we identified a catastrophic pesticide spill with the insecticide cypermethrin in the Holtemme River, Germany. Based on existing pre-event macroinvertebrate community data, we monitored the effects and recovery of the macroinvertebrate community for more than two years after the spill. Strong short-term effects were apparent for all taxa with the exception of Chironomidae and Tubificidae. Effects could also be observed on the community level as total abundance, taxa number and biomass strongly decreased. Total abundance and taxa number showed a fast recovery. Regarding long-term effects, the total biomass remained substantially below the pre-contamination level (76%) until the end of the study. Also the abundances of three taxa (Gammarus, Leuctra, Limnius Ad.) did not return to levels prior to the spill even after 26 months. This lack of the taxon-specific recovery was likely due to their long generation time and a low migration ability due to a restricted connectivity between the contaminated site and uncontaminated stream sections. These factors proved to be stronger predictors for the recovery than the pesticide tolerance. We revealed that the biological indicators SPEARpesticides and share of Ephemeroptera, Plecoptera and Trichoptera (EPT) are not suitable for the identification of such extreme events, when nearly all taxa are eradicated. Both indicators are functioning only when repeated stressors initiate long-term competitive replacement of sensitive by insensitive taxa. We conclude that pesticide spills can have significant long-term effects on stream macroinvertebrate communities. Regular ecological monitoring is imperative to identify such ecosystem impairments, combined with analytical chemistry methods to identify the potential sources of spills.

Multiple persistent organic pollutants in mothers' breastmilk: Implications for infant dietary exposure and maternal thyroid hormone homeostasis in Uganda, East Africa.

Persistent organic pollutants (POPs) are ubiquitous contaminants with adverse health effects in the ecosystem. One of such effects is endocrine disruption in humans and wildlife even at background exposure concentrations. This study assessed maternal breastmilk concentrations of POPs; brominated flame retardants (BFRs), polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs), and the potential health risks posed to the nursing infants. We also evaluated the association of these POPs with total 3,3',5-triiodo-L-thyronine (T3), L-thyroxine (T4), and 3,3',5'-triiodo-L-thyronine (rT3) levels measured in human breast milk. Thirty breastmilk samples were collected from Kampala, Uganda between August and December 2018. Hexabromobenzene was not detected while the maximum level of 2,2',4,4',5,5'-hexabrombiphenyl was 64.7 pg/g lw. The median levels of total indicator PCBs, PBDEs, dioxin-like PCBs, and PCDD/Fs in the samples were 159 pg/g lw, 511 pg/g lw, 1.16 pg TEQ/g lw, and 0.4 pg TEQ/g lw, respectively. These levels were lower than those reported in other countries. Owing to their bio accumulative nature, PCBs -81, -169, and ∑PCDD/Fs increased with increase in maternal age. Estimated dietary intakes for dioxin-like PCBs and PCDD/Fs were lower than those reported elsewhere but were higher than the WHO tolerable daily intakes suggesting potential health risks to nursing infants. In adjusted single pollutant models, PCB-126, PCB-169, and ∑PCBTEQ were negatively associated with T3, while 1,2,3,4,5,7,8-HpCDF was positively associated with rT3. Although these associations did not persist in multipollutant models, our findings suggest potential thyroid hormone disruption by POPs in mothers. This may reduce the levels of thyroid hormones transferred from the mother to the neonates and, hence, adversely influence infant growth. A temporal study with a bigger sample size is required to corroborate these findings.

Spatial, temporal, and inter-compartmental environmental monitoring of lipophilic pollutants by virtual organisms.

Sampling points belonging to the Harz National Park river system, Germany, were selected between the period of 2014 and 2017 for monitoring polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in water, air, and sediment. Triolein-containing Virtual Organisms (VO) were employed to assess the levels of chemicals in water, air and triolein as surrogate for natural fat. To avoid overestimation of the concentrations 20 performance reference compounds (PRCs)-16 PRCs-PAHs and 4 PRCs-PCBs were covering the range of properties of native compounds. Results manifested the highest concentration of individual PAH as follows: 31 ng fluoranthene/L water, 3600 ng pyrene/g fat, 62 ng phenanthrene/m3 air and 2800 ng fluoranthene/g dw sediment. All PCBs and OCPs values were below above mentioned PAH concentrations and far below EU-limit levels. Environmental partition of chemicals was investigated by calculating fugacity, suggesting a mass transport from water to air. Only quite volatile compounds such as hexachlorobutadiene showed higher fugacity in air. Ratios of sediment/water concentrations and log Kow within individual sampling periods at Holtemme River exhibited strong linear relationships. Interestingly, during summer months of the years water and fat contents well correlate to the flow rates of Holtemme River. Our results show that VO can be successfully used as a tool for ongoing exposure assessment studies and predictions of worst case levels in food and nutrition.

Placental distribution of endogenous and exogenous substances: A pilot study utilizing cryo-sampled specimen off delivery room.

INTRODUCTION: Reliability in the use of placentome (including placenta, umbilical cord, and cord blood) biomarkers requires an understanding of their distributions. Here we aim to develop a simple and proper placenta sampling scheme, and to evaluate the placental distributions of biomarkers. METHODS: We developed a continuous cooling chain protocol off delivery room and cryo-subsampling method for placenta sampling. The levels of thyroid hormones (THs), elements, persistent organic pollutants (POPs), monoamines, and vitamin E were measured using UPLC-Q-TOF-MS, HPLC-ICP-MS, HPLC-EcD, and HRGC-HRMS, respectively. The distributions of biomarkers were assessed. RESULTS: In human placentome, l-thyroxine (T4), Cd, Se, Zn, Cu, Fe, Ca, K, Mg, α-tocopherol, ß-tocopherol, and ß-tocotrienol levels were higher in placenta than in umbilical cord, while Pb and Mn were concentrated in human cord. In porcine placentome, T4, 3,3',5'-triiodo-l-thyronine (rT3), 3,3'-diiodo-l-thyronine, Cd, Pb, Zn, K, and Al levels were higher in the cord. The intraclass correlation coefficient (ICC) was <0.4 for 3,3',5-triiodo-l-thyronine, rT3, α-tocopherol, and 7 elements in human basal plate, indicating low reliability. rT3, Cd, Zn, Mn, and Cu were significantly concentrated in the central region in human placenta, while higher levels of As, Cd, Cr, and Al were found in the periphery region in porcine placenta. Polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) showed moderate reliability (ICC: 0.40-0.98) except PCB-81, -126, and BDE-208, while polychlorinated dibenzo-p-doixins/furans (PCDD/Fs) showed poor reliability (ICC: 0.07-0.31). DISCUSSION: These results highlight the complexity of placenta sampling. This study provides a novel and simple sampling approach in investigating placental exposomics.

Pine needle and semi-permeable membrane device derived organochlorine compounds (OCPs) concentrations in air in Mersin Province to Taurus, Turkey.

Organochlorine pesticides (OCPs) were analyzed in three different ages (half-, 1.5-, 2.5-year-old) for needles and semi permeable membrane devices (SPMDs) at three deployment periods from sea level to 1881 meter above sea level. Individual HCHs concentrations ranged between 1.4 and 129 pg/g fw depending on the age and sampling season while 2.5-year-old needles showed higher HCHs levels compared to half and 1.5- year-old. Correlation between elevation and HCH concentration in SPMDs was found but not in needle samples. Concentrations of HCHs in SPMDs indicated clearly cold condensation effect on accumulation in winter period and increased with altitude. Concentrations of DDTs in half and 1.5-year-old needles were lower than 2.5-year-old needles. The highest total concentration of DDTs was detected in 1-year-period SPMD. Higher concentrations were found in 2.5-year-old needles for other OCPs. Seasonal and altitude-dependent changes were not observed for other OCPs in SMPDs. Total accumulation of OCPs in SPMDs were found higher than in needles. On the contrary, an increased accumulation rate was observed for HCHs in SPMD. In general, Total concentrations of DDTs and HCHs were similar to total of other OCPs in all altitudes when dominating endosulfan wasnot taken into account in the computation of total concentration of other OCPs.

Comparative exposomics of persistent organic pollutants (PCBs, OCPs, MCCPs and SCCPs) and polycyclic aromatic hydrocarbons (PAHs) in Lake Victoria (Africa) and Three Gorges Reservoir (China).

Exposomics is assessment of organism exposure to high priority environmental pollutants in an ecosystem using OMIC technologies. A virtual organism (VO) is an artificial property-tool (OMIC) reflecting exposomic process in compartments of real organisms. The exposomics of aquatic organisms inhabiting Lake Victoria (L.V.) and Three Gorges Reservoir (TGR) were compared using VOs. The two reservoirs are heavily depended on for food and water both in Africa and China. The target priority pollutants in the reservoirs were polyclic aromatic hydrocarbons (PAHs) and persistent organic pollutants such as polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), medium chain chlorinated paraffins (MCCPs) and short chain chlorinated paraffins (SCCPs). The VOs showed that in a period of 28 days, aquatic organisms in TGR were exposed to total (∑) PAHs of 8.71 × 10-6 mg/L, PCBs of 2.81 × 10-6 mg/L, OCPs of 2.80 × 10-6 mg/L, MCCPs of 8.9 × 10-10 mg/L and SCCPs of 1.13 × 10-7 mg/L. While in a period of 48 days, organisms in L. V. were exposed to total (∑) PAHs of 7.45 × 10-6 mg/L, PCBs of 4.70 × 10-6 mg/L, OCPs of 3.39 × 10-8 mg/L, MCCPs of 4.6 × 10-10 mg/L and SCCPs of 3.6 × 10-9 mg/L. The exposomic levels in TGR after 28 days were higher than those in Lake Victoria after 48 days. In both reservoirs, bioaccumulation levels are above set standards for aquatic organisms. The sources of the pollutants into the reservoirs were diagnostically determined to originate from anthropogenic processes such as petrogenic, diesel emissions, biomass burning, coal combustion, electronic wastes, traffic emissions and historic uses.

Development and validation of a ready to use cryo-EROD assay for the standardized screening of dioxins and dioxin-like compounds in foodstuffs.

Recent European regulations have indicated the need for new bioanalytical screening methods capable of monitoring dioxin and dioxin-like compounds in foodstuffs and environmental samples, cost-effectively and with a quicker turnaround. Cryo-cells of the hepatic H4IIE line preserved in 96-well plates were exposed to sample extracts prepared from various foodstuffs and analysed for their content of dioxins and dioxin-like compounds by means of the 7-Ethoxyresorufin-O-Deethylase (EROD)-assay in two laboratories. Assay data were compared between both laboratories and results from instrumental analysis used as a confirmatory method. Additionally, cut-off values for the different studied matrices were derived. The current European regulation regarding methods of analysis for the control of foodstuffs was applied with the aim of determining the feasibility of the cryo-methodology. Results obtained in both laboratories were in congruence with the required validation parameters of the Commission Regulation (EU) No 2017/644. Cut-off values should be established matrix-dependent to reduce the rate of false compliant results and to keep the rate of false non-compliant results under control. In summary, the ready-to-use cryo-assay method for the bioanalytical screening of foodstuffs in control laboratories without cell-culture facilities has successfully proven to be accurate, far quicker and more cost effective than current methods.

Comparative study of dioxin contamination from forest soil samples (BZE II) by mass spectrometry and EROD bioassay.

Dioxins and dioxin-like compounds can be analyzed by bioanalytical screening methods to evaluate their biotoxicity. In vitro bioassays, based on 7-ethoxyresorufin-O-deethylase (EROD) and the activity of cytochrome P450 1A1 and the aryl hydrogen receptor (AhR) pathway, are employed for the evaluation of bioanalytical equivalents (BEQ) of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and polychlorinated biphenyls (PCBs) from a wide variety of sample matrices. Here, we present the evaluation of 11 humic soil samples derived from forest stands across Germany and a comparison of the BEQ values against toxic equivalents (TEQ, PCDD/Fs+PCBs) derived by chemical analysis. BEQ values ranged from 8.8 to 34.1 while TEQ values from 13.9 to 60.5 pg/g dry weight. Additional two subsequent mineral layers were analyzed to identify the BEQ/TEQ gradient vertically, showing a TEQ decrease of 85.1 and 93.8 % from the humic to the first and second mineral layers, respectively. For BEQ values, a decrease as well as an increase was detected. BEQ measurements were performed with and without sample clean-up. Omitting clean-up revealed about 20 times increased BEQ values presumably due to non-persistent bioactive compounds not detected by chemical analysis. The results we present suggest that the EROD assay can be used for the screening of large sample quantities for the identification of samples showing dioxin and dioxin-like contaminations even at low levels, which can then be further analyzed by chemical analysis to identify the congener composition. The study also shows that EROD results give a qualitative image of the contamination. EROD seems to be interfered with cross-contaminants specifically for soils with high biological activity as forest layers.

Results of the second national forest soil inventory in Germany - Interpretation of level and stock profiles for PCDD/F and PCB in terms of vegetation and humus type.

Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs) were detected in 86 humic topsoil layers and in a subset of 11 randomly selected top mineral forest soils at the depths of 0-5cm and 5-10cm collected from different federal states of Germany. The distribution of these persistent organic pollutants (POPs) in humic topsoils with respect to vegetation cover (coniferous vs. deciduous vs. mixed), total organic carbon (TOC), altitude and latitude data was investigated. There is cross correlation between the contents and TOC while the correlation with latitude indicates higher abundances of POPs in central Germany where there is high population density accompanied with industrial activities. The calculated stocks suggest that humus type (mor, mull, or moder) in conjunction with forest type can explain the relative POPs abundances in different soil layers. Generally, humic topsoils show highest contents of POPs compare to the two mineral soils with a ratio of 100:10:1. However, the stock humic layers of coniferous stands contribute about 50% to the total stock, whereas at deciduous stands the stock is mainly located in the upper mineral soil layer (0-5cm). The soil-water distribution coefficients (Kd) were calculated to estimate the potential translocation in the different soil types. The Kd values vary among the PCBs and PCDD/Fs congeners and are most variable for humic topsoils. There is pronounced chemical abundance in the top mineral soils with increasing Kd and this points to non-water bound transport processes for superlipophilic compounds.

Photodegradative fate and potential phototoxic products of bromocarbazoles and chlorocarbazoles in water.

Bromocarbazoles and chlorocarbazoles are emerging environmental contaminants that have been reported to be persistent and possessing dioxin-like toxicity; however, their photodegradative fate in water is unknown. The photodegradation of 3-bromocarbazole, 3-chlorocarbazole, and 3,6-dichlorocarbazole was determined in ultrapure water. They proceeded by direct photolysis and followed first-order kinetics. The rate constants (k) were 0.4838, 0.3454, and 0.4422 h-1 corresponding to half-lives (t 1/2) 1.81, 2.01, and 1.62, while the quantum yields (Ф) were 0.232, 0.180, and 0.295 respectively. The maximum wavelengths of absorption (λ max) were in the near ultraviolet region (295, 296, 299, and 301 nm) implying these compounds are likely to degrade slowly under sunlight in natural aquatic environment. The molar extinction coefficients (ε) determined in acetonitrile were 18,573, 17,028, 13,385, and 14,010 L mol-1 cm-1, respectively, the latter being 3,6-dibromocarbazole. A bathochromic shift was observed with halogen addition on their respective mono-substituted congeners. Bromocarbazoles were observed to degrade faster in water than chlorocarbazoles. In addition, photodegradation was estimated to proceed faster in summer than in winter, in natural water system at 50° N latitude. In the absence of light, hydrolytic degradation occurred but proceeded very slowly. Hexahydroxybenzene and trihydroxycarbazole were positively identified as the likely photoproducts with the former being a known toxic compound. Dehalogenation, oxidative cleavage, hydroxylation, and hydrolysis are suggested as the major photodegradation mechanisms in water, yielding phototoxic products that may be of enhanced toxicity than the parent compounds.

Adapting current model with field data of related performance reference compounds in passive samplers to accurately monitor hydrophobic organic compounds in aqueous media.

Performance reference compounds (PRCs) are neutral organic compounds, introduced in a passive sampler prior deployment for the assessment of in situ sampling rate. In this study, evaluation of in situ sampling rates of 16 13C-PAH-PRCs with moderate and high hydrophobicity was established to provide an overall correction factor for variations in virtual organism (VO) uptake rates of the analytes of interest. In situ sampling rate was compared to an empirical model during sampling campaign in 2011 with VO in 12 different sites along the Three Gorges Reservoir (TGR) in China. A discrepancy was observed for high hydrophobic compounds with log K ow ranging from 5.18 to 6.63 where ΣPAH concentration in TGR from Huckins model (305,624 pg/L) was resulted to be roughly 2-fold higher than the alternative procedure (182,292 pg/L). A relationship between in situ sampling rates of the 16 13C-PAH-PRCs (Rs, PRC ) and log K ow was set up to allow then calculation of analyte sampling rate Rs analyte (N) of various organic pollutants with log K ow  ≤ 6.63.

Monitoring of organic pollutants in marine environment by semipermeable membrane devices and mussels: accumulation and biochemical responses.

This study involves the monitoring of organic pollutants using transplanted mussels (Mytilus galloprovincialis) as bioindicator organisms and semipermeable membrane devices (SPMDs) as passive samplers. Mussels and SPMDs were deployed to marinas, shipyards and shipbreaking yards on the coastal area of Turkey and retrieved after 60 days. Polycyclic aromatic hydrocarbons (PAH), polychlorinated biphenyls (PCB) and organochlorine pesticide (OCP) compounds were analysed with high-resolution GC-MS. Total PAH concentrations in SPMDs and mussels ranged from 200 to 4740 ng g sampler-1 and from 7.0 to 1130 ng g-1 in wet weight (ww). PCB and OCP concentrations in SPMDs changed between 0.04-200 and 4.0-26 ng g sampler-1, respectively. The highest PCB (190 ng g-1 ww) and OCP (200 ng g-1 ww) concentrations in mussels were measured at shipyard stations. A strong correlation was observed between the PAH and PCB concentrations in SPMDs and mussels. Enzyme assays (acetylcholinesterase, ethoxyresorufin-O-deethylase, glutathione S-transferase, glutathion reductase and carboxylesterase activities) were performed as biomarkers to reveal the effects of pollution on the mussels. There was no clear relationship found between the enzyme levels and the pollutant concentrations in mussels. Integrated biomarker responses were calculated to interpret the overall effect of pollutants.

Polycyclic aromatic hydrocarbons (PAHs) determined by pine needles and semipermeable membrane devices along an altitude profile in Taurus Mountains, Turkey.

Polycyclic aromatic hydrocarbons (PAHs) were analyzed at different altitudes of Taurus Mountains in semipermeable membrane devices (SPMD) and in half-, one-and-a-half-, and two-and-a-half-year-old pine needles. SPMDs were deployed for three different exposure periods: March to September (Summer), September to March (Winter), and March to March (whole year) at eight sites where needle samples were collected. The values of PAHs in needles were between 4.4 to 6066 pg g/fw in half-year-old, 7.2 to 111,115 pg g/fw in 1.5-year-old, and 9.7 to 85,335 pg g/fw in 2.5-year-old needles. Mass of PAHs collected by SPMDs varied from

Persistent organic pollutants in shallow percolated water of the Alps Karst system (Zugspitze summit, Germany).

In the German Calcareous Alps at the Zugspitze, percolated water close to a permafrost bedrock in a tunnel system was monitored long-term for polychlorinated dibenzo-p-dioxins (PCDD), polychlorinated dibenzofurans (PCDF), polychlorinated biphenyls (PCB), polycyclic aromatic hydrocarbons (PAH), and 28 organochlorine pesticides (OCP). Semi-permeable membrane devices (SPMD) were deployed in a temporary surface water system at the Zugspitze plateau and analysed for PCB, PAH, and OCP. The high-volume water sampling was successfully implemented and all compounds were identified in the water percolated through the Karst system. However, the percentage distribution of contaminants in the percolated water differed significantly from that found in surface waters. The highest chlorinated PCDD homologues were the predominant compounds of the PCDD/F family, whereas percentages of PCB #52 increased in percolated water. Toxic equivalent values (TEQ) of samples ranged from 2.0 to 4.2pgTEQ/m3 and from 0.017 to 0.069pgTEQ/m3 for PCDD/F and PCB, respectively. Low and intermediate molecular weight PAH were the prevailing compounds in the samples. Endosulfan sulfate, endrin, and cis-heptachlor epoxide were enhanced after water percolation through the Karst system in comparison with the surface waters (wet deposition). The relative enrichment on these pesticides was related to the environmental bedrock conditions and glacier melting sources. In summary, the Karst system highly influenced the fate of organic persistent pollutants generating different chemical patterns in their percolated waters than those found at the surface systems.

The fingerprints of dioxin-like bromocarbazoles and chlorocarbazoles in selected forest soils in Germany.

The occurrence of bromocarbazoles and chlorocarbazoles was studied in 86 forest soil samples from different regions in Germany. Carbazole, 3-chlorocarbazole, 3-bromocarbazole and 3,6-dibromocarbazole were qualitatively detected in the humic layer of 59 soil samples with bromocarbazoles reported here for the first time in soil. Furthermore, the halogenated carbazoles, PCDD/Fs and PCBs were detected in the humic and mineral soil horizons (0-5 cm and 5-10 cm) of a subset of 11 soil samples subjected to quantitative analysis. Concentrations ranged from 0.6 to 267.6 ng/g (carbazole); 0.2-7.2 ng/g (3-bromocarbazole); 0.0-9.1 ng/g (3-chlorocarbazole); 0.2-19.8 ng/g (3,6-dibromocarbazole); 0.4-67.6 ng/g (3,6-dichlorocarbazole); 0.0-0.7 ng/g (PCDDs); 0.0-0.3 ng/g (PCDFs) and 0.0-33.7 ng/g (PCBs). Concentrations decreased with depth and correlated positively to total organic carbon (TOC). When it was based on TOC%, an increase in concentration with depth was observed in most soil samples. With respect to dioxin-like toxicity, 3-bromocarbazole, 3-chlorocarbazole, 3,6-dibromocarbazole and 3,6-dichlorocarbazoles caused induction of CYP1A1-dependent EROD activity in HII4E rat hepatoma cell line. Their relative effect potency after 72 h exposure ranged from 0.00005 to 0.00013 and was directly related to the degree of halogenation with 2,3,7,8-tetrachlorodibenzo-p-dioxin as reference. Furthermore, their contribution to overall soil dioxin-like toxicity was not significant in comparison to PCDD/Fs and PCBs though the sum toxic equivalency was limited to three halogenated carbazole congeners. Bromocarbazoles and chlorocarbazoles are emerging dioxin-like toxic environmental contaminants with potential for wide distribution occurring simultaneously with PCDD/Fs and PCBs.